The present invention relates to electrically energized electromagnetically actuated valves for service in appliances such as icemakers employed in household refrigerators. Valves of the aforesaid type are required to operate with a low wattage power consumption and to be compact and inexpensive to manufacture. In particular, electromagnetically actuated valves employed for use in refrigerator icemakers are required to provide long life when connected to water supplies of varying impurity and chemical content. Heretofore, electromagnetically actuated valves for refrigerator icemakers have employed a solenoid actuated poppet and a valving chamber formed in the plastic valve body with a plastic guide closing the valving chamber and functioning as a guide for the movable armature.
Valves of the aforesaid type typically employ a ferromagnetic member for the armature with the poppet formed on one end thereof; and, a resilient elastomeric seat is usually provided in the valving chamber for contact by the poppet for performing the valving function. A valve construction of the aforementioned type is shown and described in U.S. Pat. No. 4,697,608 and commonly assigned to the Assignee of the present application. However, difficulties have been encountered in manufacturing such a valve construction in assembling the valve seat, armature and plastic armature guide for closing the valving chamber onto the body of the valve. In particular, problems have been encountered in assembling the valve seat into the body and providing a static seal therearound for preventing flow bypassing of the valve seat for the poppet and leakage to the valve outlet when the poppet is in the closed position and seated on the elastomeric valve seat.
In addition, in providing elastomeric valve seats in valves of the aforementioned type, problems have been encountered with deformation of the valve seat under the forces of the line pressure of the water acting against the valve seat when the valve is in the closed position. Where unusually high water line pressures are encountered in a particular water supply line, deformation of the elastomeric valve seat has been experienced. In numerous instances, the deformation has been sufficient to either restrict or close the outlet of the valve seat so that an adequate flow of water cannot pass when the poppet is lifted from the valve seat upon energization of the solenoid.
Furthermore, problems have been encountered in manufacturing of valves of the aforementioned type in assembling the valve seat, poppet/armature and the plastic valve guide member for closing the valving chamber onto the valve body.
Thus, it has been desired to find a way or means of enabling economical and reliable assembly of an electromagnetically actuated solenoid operated appliance water valve having an elastomeric valve seat. It has been further desired to provide a construction for such a valve in which the elastomeric valve seat is not distorted so as to be rendered inoperative during assembly or when exposed to unusually high water line pressures in service.
Additionally, in appliance water valves of the aforementioned type it has been desired to find a way or means of economically and rigidly retaining and fastening the ferromagnetic pole frame over the non-metallic armature guide in a manner which eliminates the need for separate fasteners and avoids undue strain on the armature guide.